This is the 4th group of driver conversion examples. This set is
complete, as there are only a few drivers which use __register_blkdev().
The __register_blkdev() call uses an optional probe call, and if set
will be used when blk_request_module() is called for the block device.
Since these probe calls can fail, now that we added *add_disk*() error
handling, take advatage of this and extend the probe call to capture
the errors.
There are only a few drivers which benefit from this. The meat of the
work is the last patch, which includes all driver conversions. The rest
of the patches are adding add_disk() error handling in the other
places of the drivers.
Luis Chamberlain (12):
floppy: fix add_disk() assumption on exit
floppy: use blk_cleanup_disk()
floppy: add error handling support for add_disk()
scsi/sd: use blk_cleanup_queue() insted of put_disk()
scsi/sd: add error handling support for add_disk()
scsi/sr: use blk_cleanup_disk() instead of put_disk()
scsi/sr: add error handling support for add_disk()
block/ataflop: use the blk_cleanup_disk() helper
block/ataflop: add a helper for removing disks
block/ataflop add error handling support for add_disk()
block/brd: add error handling support for add_disk()
block: make probe in blk_request_module() return an error
block/genhd.c | 15 ++++++----
drivers/block/ataflop.c | 66 ++++++++++++++++++++++++-----------------
drivers/block/brd.c | 17 ++++++++---
drivers/block/floppy.c | 48 ++++++++++++++----------------
drivers/block/loop.c | 6 ++--
drivers/scsi/sd.c | 11 +++++--
drivers/scsi/sr.c | 7 +++--
fs/block_dev.c | 5 +++-
include/linux/genhd.h | 4 +--
9 files changed, 105 insertions(+), 74 deletions(-)
--
2.27.0
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
We take advantage of the new ability of del_gendisk() ...
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/block/floppy.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index ba690affc751..cad17b49e700 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4478,6 +4478,7 @@ static const struct blk_mq_ops floppy_mq_ops = {
};
static struct platform_device floppy_device[N_DRIVE];
+static bool registered[N_DRIVE];
static bool floppy_available(int drive)
{
@@ -4693,8 +4694,12 @@ static int __init do_floppy_init(void)
if (err)
goto out_remove_drives;
- device_add_disk(&floppy_device[drive].dev, disks[drive][0],
- NULL);
+ registered[drive] = true;
+
+ err = device_add_disk(&floppy_device[drive].dev,
+ disks[drive][0], NULL);
+ if (err)
+ goto out_remove_drives;
}
return 0;
@@ -4703,7 +4708,8 @@ static int __init do_floppy_init(void)
while (drive--) {
if (floppy_available(drive)) {
del_gendisk(disks[drive][0]);
- platform_device_unregister(&floppy_device[drive]);
+ if (registered[drive])
+ platform_device_unregister(&floppy_device[drive]);
}
}
out_release_dma:
@@ -4946,7 +4952,8 @@ static void __exit floppy_module_exit(void)
if (disks[drive][i])
del_gendisk(disks[drive][i]);
}
- platform_device_unregister(&floppy_device[drive]);
+ if (registered[drive])
+ platform_device_unregister(&floppy_device[drive]);
}
for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
if (disks[drive][i])
--
2.27.0
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/scsi/sr.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 362f04a3761a..ed097b69821e 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -776,7 +776,10 @@ static int sr_probe(struct device *dev)
dev_set_drvdata(dev, cd);
disk->flags |= GENHD_FL_REMOVABLE;
sr_revalidate_disk(cd);
- device_add_disk(&sdev->sdev_gendev, disk, NULL);
+
+ error = device_add_disk(&sdev->sdev_gendev, disk, NULL);
+ if (error)
+ goto fail_minor;
sdev_printk(KERN_DEBUG, sdev,
"Attached scsi CD-ROM %s\n", cd->cdi.name);
--
2.27.0
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
We reuse the atari_floppy_disk_remove() call.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/block/ataflop.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 73eb80b58888..4b3f1158fa04 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -2081,7 +2081,9 @@ static int __init atari_floppy_init (void)
for (i = 0; i < FD_MAX_UNITS; i++) {
unit[i].track = -1;
unit[i].flags = 0;
- add_disk(unit[i].disk[0]);
+ ret = add_disk(unit[i].disk[0]);
+ if (ret)
+ goto err_out_dma;
}
printk(KERN_INFO "Atari floppy driver: max. %cD, %strack buffering\n",
@@ -2091,13 +2093,10 @@ static int __init atari_floppy_init (void)
return 0;
+err_out_dma:
+ atari_stram_free(DMABuffer);
err:
- while (--i >= 0) {
- blk_cleanup_disk(unit[i].disk[0]);
- blk_mq_free_tag_set(&unit[i].tag_set);
- }
-
- unregister_blkdev(FLOPPY_MAJOR, "fd");
+ atari_floppy_disk_remove();
out_unlock:
mutex_unlock(&ataflop_probe_lock);
return ret;
--
2.27.0
This makes the probe callback use din blk_request_module() return
an error. We do this as add_disk() now has error handling, and
so we can bail earlier than before. If a probe is not implemented
then its not used.
This is mostly useful for the following drivers:
* ataflop
* brd
* floppy
* loop
* scsi/sd
Signed-off-by: Luis Chamberlain <[email protected]>
---
block/genhd.c | 15 +++++++++------
drivers/block/ataflop.c | 20 +++++++++++++++-----
drivers/block/brd.c | 7 +++++--
drivers/block/floppy.c | 14 ++++++++++----
drivers/block/loop.c | 6 +++---
drivers/scsi/sd.c | 3 ++-
fs/block_dev.c | 5 ++++-
include/linux/genhd.h | 4 ++--
8 files changed, 50 insertions(+), 24 deletions(-)
diff --git a/block/genhd.c b/block/genhd.c
index 72703d243b44..ca6393df09ad 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -161,7 +161,7 @@ static struct blk_major_name {
struct blk_major_name *next;
int major;
char name[16];
- void (*probe)(dev_t devt);
+ int (*probe)(dev_t devt);
} *major_names[BLKDEV_MAJOR_HASH_SIZE];
static DEFINE_MUTEX(major_names_lock);
@@ -190,7 +190,7 @@ void blkdev_show(struct seq_file *seqf, off_t offset)
* @major: the requested major device number [1..BLKDEV_MAJOR_MAX-1]. If
* @major = 0, try to allocate any unused major number.
* @name: the name of the new block device as a zero terminated string
- * @probe: allback that is called on access to any minor number of @major
+ * @probe: callback that is called on access to any minor number of @major
*
* The @name must be unique within the system.
*
@@ -208,7 +208,7 @@ void blkdev_show(struct seq_file *seqf, off_t offset)
* Use register_blkdev instead for any new code.
*/
int __register_blkdev(unsigned int major, const char *name,
- void (*probe)(dev_t devt))
+ int (*probe)(dev_t devt))
{
struct blk_major_name **n, *p;
int index, ret = 0;
@@ -728,17 +728,18 @@ static ssize_t disk_badblocks_store(struct device *dev,
return badblocks_store(disk->bb, page, len, 0);
}
-void blk_request_module(dev_t devt)
+int blk_request_module(dev_t devt)
{
unsigned int major = MAJOR(devt);
struct blk_major_name **n;
+ int err;
mutex_lock(&major_names_lock);
for (n = &major_names[major_to_index(major)]; *n; n = &(*n)->next) {
if ((*n)->major == major && (*n)->probe) {
- (*n)->probe(devt);
+ err = (*n)->probe(devt);
mutex_unlock(&major_names_lock);
- return;
+ return err;
}
}
mutex_unlock(&major_names_lock);
@@ -746,6 +747,8 @@ void blk_request_module(dev_t devt)
if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
/* Make old-style 2.4 aliases work */
request_module("block-major-%d", MAJOR(devt));
+
+ return 0;
}
/*
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 4b3f1158fa04..ce08b8e60163 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -2005,22 +2005,32 @@ static void atari_floppy_disk_remove(void)
}
-static void ataflop_probe(dev_t dev)
+static int ataflop_probe(dev_t dev)
{
int drive = MINOR(dev) & 3;
int type = MINOR(dev) >> 2;
+ int err = -ENODEV;
if (type)
type--;
- if (drive >= FD_MAX_UNITS || type >= NUM_DISK_MINORS)
- return;
+ if (drive >= FD_MAX_UNITS || type >= NUM_DISK_MINORS) {
+ err = -EINVAL;
+ goto out;
+ }
+
mutex_lock(&ataflop_probe_lock);
if (!unit[drive].disk[type]) {
- if (ataflop_alloc_disk(drive, type) == 0)
- add_disk(unit[drive].disk[type]);
+ if (ataflop_alloc_disk(drive, type) == 0) {
+ err = add_disk(unit[drive].disk[type]);
+ if (err)
+ blk_cleanup_disk(unit[drive].disk[type]);
+ }
}
mutex_unlock(&ataflop_probe_lock);
+
+out:
+ return err;
}
static int __init atari_floppy_init (void)
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index ca017ca315c5..104adf70a15a 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -429,10 +429,11 @@ static int brd_alloc(int i)
return err;
}
-static void brd_probe(dev_t dev)
+static int brd_probe(dev_t dev)
{
int i = MINOR(dev) / max_part;
struct brd_device *brd;
+ int err = 0;
mutex_lock(&brd_devices_mutex);
list_for_each_entry(brd, &brd_devices, brd_list) {
@@ -440,9 +441,11 @@ static void brd_probe(dev_t dev)
goto out_unlock;
}
- brd_alloc(i);
+ err = brd_alloc(i);
out_unlock:
mutex_unlock(&brd_devices_mutex);
+
+ return err;
}
static void brd_del_one(struct brd_device *brd)
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index cad17b49e700..52bc645f3060 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4517,21 +4517,27 @@ static int floppy_alloc_disk(unsigned int drive, unsigned int type)
static DEFINE_MUTEX(floppy_probe_lock);
-static void floppy_probe(dev_t dev)
+static int floppy_probe(dev_t dev)
{
unsigned int drive = (MINOR(dev) & 3) | ((MINOR(dev) & 0x80) >> 5);
unsigned int type = (MINOR(dev) >> 2) & 0x1f;
+ int err;
if (drive >= N_DRIVE || !floppy_available(drive) ||
type >= ARRAY_SIZE(floppy_type))
- return;
+ return -EINVAL;
mutex_lock(&floppy_probe_lock);
if (!disks[drive][type]) {
- if (floppy_alloc_disk(drive, type) == 0)
- add_disk(disks[drive][type]);
+ if (floppy_alloc_disk(drive, type) == 0) {
+ err = add_disk(disks[drive][type]);
+ if (err)
+ blk_cleanup_disk(disks[drive][type]);
+ }
}
mutex_unlock(&floppy_probe_lock);
+
+ return err;
}
static int __init do_floppy_init(void)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index efbd8e29aca7..081cccd39bc9 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -2358,13 +2358,13 @@ static void loop_remove(struct loop_device *lo)
kfree(lo);
}
-static void loop_probe(dev_t dev)
+static int loop_probe(dev_t dev)
{
int idx = MINOR(dev) >> part_shift;
if (max_loop && idx >= max_loop)
- return;
- loop_add(idx);
+ return -EINVAL;
+ return loop_add(idx);
}
static int loop_control_remove(int idx)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 01af61a38e4e..800dfd5984bd 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -633,8 +633,9 @@ static struct scsi_driver sd_template = {
* Don't request a new module, as that could deadlock in multipath
* environment.
*/
-static void sd_default_probe(dev_t devt)
+static int sd_default_probe(dev_t devt)
{
+ return 0;
}
/*
diff --git a/fs/block_dev.c b/fs/block_dev.c
index c41d0e550d39..531feb097cb2 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1326,10 +1326,13 @@ struct block_device *blkdev_get_no_open(dev_t dev)
{
struct block_device *bdev;
struct gendisk *disk;
+ int err;
bdev = bdget(dev);
if (!bdev) {
- blk_request_module(dev);
+ err = blk_request_module(dev);
+ if (err)
+ return NULL;
bdev = bdget(dev);
if (!bdev)
return NULL;
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 73024416d2d5..9db56d4562ae 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -312,7 +312,7 @@ struct gendisk *__blk_alloc_disk(int node);
void blk_cleanup_disk(struct gendisk *disk);
int __register_blkdev(unsigned int major, const char *name,
- void (*probe)(dev_t devt));
+ int (*probe)(dev_t devt));
#define register_blkdev(major, name) \
__register_blkdev(major, name, NULL)
void unregister_blkdev(unsigned int major, const char *name);
@@ -342,7 +342,7 @@ static inline void bd_unlink_disk_holder(struct block_device *bdev,
dev_t part_devt(struct gendisk *disk, u8 partno);
dev_t blk_lookup_devt(const char *name, int partno);
-void blk_request_module(dev_t devt);
+int blk_request_module(dev_t devt);
#ifdef CONFIG_BLOCK
void printk_all_partitions(void);
#else /* CONFIG_BLOCK */
--
2.27.0
Use the helper to replace two lines with one.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/block/ataflop.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index a093644ac39f..abb6fde0bd81 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -2076,8 +2076,7 @@ static int __init atari_floppy_init (void)
err:
while (--i >= 0) {
- blk_cleanup_queue(unit[i].disk[0]->queue);
- put_disk(unit[i].disk[0]);
+ blk_cleanup_disk(unit[i].disk[0]);
blk_mq_free_tag_set(&unit[i].tag_set);
}
@@ -2135,8 +2134,7 @@ static void __exit atari_floppy_exit(void)
if (!unit[i].disk[type])
continue;
del_gendisk(unit[i].disk[type]);
- blk_cleanup_queue(unit[i].disk[type]->queue);
- put_disk(unit[i].disk[type]);
+ blk_cleanup_disk(unit[i].disk[0]);
}
blk_mq_free_tag_set(&unit[i].tag_set);
}
--
2.27.0
Use the blk_cleanup_queue() followed by put_disk() can be
replaced with blk_cleanup_disk(). No need for two separate
loops.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/block/floppy.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index b68f4b6bf737..ba690affc751 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4950,13 +4950,9 @@ static void __exit floppy_module_exit(void)
}
for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
if (disks[drive][i])
- blk_cleanup_queue(disks[drive][i]->queue);
+ blk_cleanup_disk(disks[drive][i]);
}
blk_mq_free_tag_set(&tag_sets[drive]);
- for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
- if (disks[drive][i])
- put_disk(disks[drive][i]);
- }
}
cancel_delayed_work_sync(&fd_timeout);
--
2.27.0
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/block/brd.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 95694113e38e..ca017ca315c5 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -375,6 +375,7 @@ static int brd_alloc(int i)
struct brd_device *brd;
struct gendisk *disk;
char buf[DISK_NAME_LEN];
+ int err = -ENOMEM;
brd = kzalloc(sizeof(*brd), GFP_KERNEL);
if (!brd)
@@ -413,14 +414,19 @@ static int brd_alloc(int i)
/* Tell the block layer that this is not a rotational device */
blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, disk->queue);
- add_disk(disk);
+ err = add_disk(disk);
+ if (err)
+ goto out_cleanup_disk;
+
list_add_tail(&brd->brd_list, &brd_devices);
return 0;
+out_cleanup_disk:
+ blk_cleanup_disk(disk);
out_free_dev:
kfree(brd);
- return -ENOMEM;
+ return err;
}
static void brd_probe(dev_t dev)
--
2.27.0
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/scsi/sd.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 6d0a82da7131..01af61a38e4e 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -3489,7 +3489,11 @@ static int sd_probe(struct device *dev)
pm_runtime_set_autosuspend_delay(dev,
sdp->host->hostt->rpm_autosuspend_delay);
}
- device_add_disk(dev, gd, NULL);
+
+ error = device_add_disk(dev, gd, NULL);
+ if (error)
+ goto out_free_index;
+
if (sdkp->capacity)
sd_dif_config_host(sdkp);
--
2.27.0
The single put_disk() is useful if you know you're not doing
a cleanup after add_disk(), but since we want to add support
for that, just use the normal form of blk_cleanup_disk() to
cleanup the queue and put the disk.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/scsi/sr.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 94c254e9012e..362f04a3761a 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -789,7 +789,7 @@ static int sr_probe(struct device *dev)
clear_bit(minor, sr_index_bits);
spin_unlock(&sr_index_lock);
fail_put:
- put_disk(disk);
+ blk_cleanup_disk(disk);
mutex_destroy(&cd->lock);
fail_free:
kfree(cd);
--
2.27.0
The single put_disk() is useful if you know you're not doing
a cleanup after add_disk(), but since we want to add support
for that, just use the normal form of blk_cleanup_disk() to
cleanup the queue and put the disk.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/scsi/sd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 6d2d63629a90..6d0a82da7131 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -3510,7 +3510,7 @@ static int sd_probe(struct device *dev)
out_free_index:
ida_free(&sd_index_ida, index);
out_put:
- put_disk(gd);
+ blk_cleanup_disk(gd);
out_free:
sd_zbc_release_disk(sdkp);
kfree(sdkp);
--
2.27.0
The del_gendisk() can be used now safely even if add_disk()
did not complete, and so using a helper allows other code to
use this later.
Signed-off-by: Luis Chamberlain <[email protected]>
---
drivers/block/ataflop.c | 31 ++++++++++++++++++-------------
1 file changed, 18 insertions(+), 13 deletions(-)
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index abb6fde0bd81..73eb80b58888 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -1988,6 +1988,23 @@ static int ataflop_alloc_disk(unsigned int drive, unsigned int type)
static DEFINE_MUTEX(ataflop_probe_lock);
+static void atari_floppy_disk_remove(void)
+{
+ int i, type;
+
+ for (i = 0; i < FD_MAX_UNITS; i++) {
+ for (type = 0; type < NUM_DISK_MINORS; type++) {
+ if (!unit[i].disk[type])
+ continue;
+ del_gendisk(unit[i].disk[type]);
+ blk_cleanup_disk(unit[i].disk[0]);
+ }
+ blk_mq_free_tag_set(&unit[i].tag_set);
+ }
+ unregister_blkdev(FLOPPY_MAJOR, "fd");
+
+}
+
static void ataflop_probe(dev_t dev)
{
int drive = MINOR(dev) & 3;
@@ -2127,19 +2144,7 @@ __setup("floppy=", atari_floppy_setup);
static void __exit atari_floppy_exit(void)
{
- int i, type;
-
- for (i = 0; i < FD_MAX_UNITS; i++) {
- for (type = 0; type < NUM_DISK_MINORS; type++) {
- if (!unit[i].disk[type])
- continue;
- del_gendisk(unit[i].disk[type]);
- blk_cleanup_disk(unit[i].disk[0]);
- }
- blk_mq_free_tag_set(&unit[i].tag_set);
- }
- unregister_blkdev(FLOPPY_MAJOR, "fd");
-
+ atari_floppy_disk_remove();
del_timer_sync(&fd_timer);
atari_stram_free( DMABuffer );
}
--
2.27.0